<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8"/>
    <title>sessionStorage</title>
</head>
<body>
<h2>sessionStorage</h2>
<button onclick="saveData()">点我保存一个数据</button>
<button onclick="readData()">点我读取一个数据</button>
<button onclick="deleteData()">点我删除一个数据</button>
<button onclick="deleteAllData()">点我清空一个数据</button>

<script type="text/javascript">
    let p = {name: '张三', age: 18}

    function saveData() {
        sessionStorage.setItem('msg', 'hello!!!')
        sessionStorage.setItem('msg2', 666)
        sessionStorage.setItem('person', JSON.stringify(p))
    }

    function readData() {
        console.log(sessionStorage.getItem('msg'))
        console.log(sessionStorage.getItem('msg2'))

        const result = sessionStorage.getItem('person')
        console.log(JSON.parse(result))

        // console.log(sessionStorage.getItem('msg3'))
    }

    function deleteData() {
        sessionStorage.removeItem('msg2')
    }

    function deleteAllData() {
        sessionStorage.clear()
    }
</script>
</body>
</html>